>This is really different though in that this code is all open source.
Open source or proprietary you still have to respect the license.
>The argument is that sufficient code is being verbatim copies so as to be a derivative work.
Yeah, it also depends what derivative work means, I could make a script that inputs MS code and outputs it with obfuscation, is it derivative work or will MS complain that is not enough and I did not had permission to do this,
AFAIK code on GitHub does not have the permssions to be used as input for copilot, and not all code there has the permissions from all authors to be hosted there.
What MS should do is
1 use their proprietary repos as input too to show us that they think the results are derivative code
2 use their customer private code too to prove again that they are ready to prove in court that this is derivative work
3 open the model with no restrictions, then we could say MS is doing it for the advancement of society and sure charge for the service
4 promise to defend any developer in case their AI outputs copyrighted content.